kml_decode.c

《嵌入式系统设计与实例开发实验教材二源码》Linux内核移植与编译实验

/*
 * KML Decoding
 *
 * Copryright (C) 1996 Arthur Ma <[e-mail]> 
 *
 * Copyright (C) 2001 Mountainview Data, Inc.
 */
#define __NO_VERSION__
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/intermezzo_fs.h>
#include <linux/intermezzo_kml.h>

static int size_round (int val);
static int unpack_create (struct kml_create *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_open (struct kml_open *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_symlink (struct kml_symlink *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_mknod (struct kml_mknod *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_link (struct kml_link *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_rename (struct kml_rename *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_unlink (struct kml_unlink *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_rmdir (struct kml_rmdir *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_setattr (struct kml_setattr *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_close (struct kml_close *rec, char *buf,
                                int pos, int *rec_offs);
static int unpack_mkdir (struct kml_mkdir *rec, char *buf,
                                int pos, int *rec_offs);

#if 0
static int unpack_endmark (struct kml_endmark *rec, char *buf,
                                int pos, int *rec_offs);
static void print_kml_endmark (struct kml_endmark *rec);
#endif

static int kml_unpack (char *kml_buf, int rec_size, int kml_offset,
                        struct kml_rec **newrec);
static char *kml_version (struct presto_version *ver);
static void print_kml_prefix (struct big_journal_prefix *head);
static void print_kml_create (struct kml_create *rec);
static void print_kml_mkdir (struct kml_mkdir *rec);
static void print_kml_unlink (struct kml_unlink *rec);
static void print_kml_rmdir (struct kml_rmdir *rec);
static void print_kml_close (struct kml_close *rec);
static void print_kml_symlink (struct kml_symlink *rec);
static void print_kml_rename (struct kml_rename *rec);
static void print_kml_setattr (struct kml_setattr *rec);
static void print_kml_link (struct kml_link *rec);
static void print_kml_mknod (struct kml_mknod *rec);
static void print_kml_open (struct kml_open *rec);
static void print_kml_suffix (struct journal_suffix *tail);
static char *readrec (char *recbuf, int reclen, int pos, int *size);

#define  KML_PREFIX_WORDS           8
static int kml_unpack (char *kml_buf, int rec_size, int kml_offset, 
                        struct kml_rec **newrec)
{
        struct kml_rec  *rec;
        char            *p;
        int             pos, rec_offs;
        int             error;

        ENTRY;
        if (rec_size < sizeof (struct journal_prefix) +
                       sizeof (struct journal_suffix))
                return -EBADF;

        PRESTO_ALLOC(rec, struct kml_rec *, sizeof (struct kml_rec));
        if (rec == NULL) {
                EXIT;
                return -ENOMEM;
        }
        rec->rec_kml_offset = kml_offset;
        rec->rec_size = rec_size;
        p = kml_buf;
        p = dlogit (&rec->rec_head, p, KML_PREFIX_WORDS * sizeof (int));
        p = dlogit (&rec->rec_head.groups, p, 
                        sizeof (int) * rec->rec_head.ngroups);

        pos = sizeof (struct journal_prefix) + 
                        sizeof (int) * rec->rec_head.ngroups;
        switch (rec->rec_head.opcode)
        {
                case KML_CREATE:
                        error = unpack_create (&rec->rec_kml.create, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_MKDIR:
                        error = unpack_mkdir (&rec->rec_kml.mkdir, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_UNLINK:
                        error = unpack_unlink (&rec->rec_kml.unlink, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_RMDIR:
                        error = unpack_rmdir (&rec->rec_kml.rmdir, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_CLOSE:
                        error = unpack_close (&rec->rec_kml.close, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_SYMLINK:
                        error = unpack_symlink (&rec->rec_kml.symlink, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_RENAME:
                        error = unpack_rename (&rec->rec_kml.rename, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_SETATTR:
                        error = unpack_setattr (&rec->rec_kml.setattr, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_LINK:
                        error = unpack_link (&rec->rec_kml.link, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_OPEN:
                        error = unpack_open (&rec->rec_kml.open, 
                                        kml_buf, pos, &rec_offs);
                        break;
                case KML_MKNOD:
                        error = unpack_mknod (&rec->rec_kml.mknod, 
                                        kml_buf, pos, &rec_offs);
                        break;
#if 0
                case KML_ENDMARK:
                        error = unpack_endmark (&rec->rec_kml.endmark, 
                                        kml_buf, pos, &rec_offs);
                        break;
#endif
                default:
                        CDEBUG (D_KML, "wrong opcode::%u\n", 
                                        rec->rec_head.opcode);
                        EXIT;
                        return -EINVAL;
        } 
        if (error) {
                PRESTO_FREE (rec, sizeof (struct kml_rec));
                return -EINVAL;
        }
        p = kml_buf + rec_offs;
        p = dlogit (&rec->rec_tail, p, sizeof (struct journal_suffix));
        memset (&rec->kml_optimize, 0, sizeof (struct kml_optimize));
        *newrec = rec;
        EXIT;
        return 0;
}

static int size_round (int val)
{
        return (val + 3) & (~0x3);
}

static int unpack_create (struct kml_create *rec, char *buf, 
                                int pos, int *rec_offs)
{
        char *p, *q;
        int unpack_size = 88;
        int pathlen;

        ENTRY;
        p = buf + pos;
        p = dlogit (&rec->old_parentv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_parentv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_objectv, p, sizeof (struct presto_version));
        p = dlogit (&rec->mode, p, sizeof (int));
        p = dlogit (&rec->uid, p, sizeof (int));
        p = dlogit (&rec->gid, p, sizeof (int));
        p = dlogit (&pathlen, p, sizeof (int));

        PRESTO_ALLOC(q, char *, pathlen + 1);
        if (q == NULL) {
                EXIT;
                return -ENOMEM;
        }

        memcpy (q, p, pathlen);
        q[pathlen] = '\0';
        rec->path = q;

        *rec_offs = pos + unpack_size + size_round(pathlen);
        EXIT;
        return 0;
}

static int unpack_open (struct kml_open *rec, char *buf, 
                                int pos, int *rec_offs)
{
        *rec_offs = pos;
        return 0;
}

static int unpack_symlink (struct kml_symlink *rec, char *buf, 
                                int pos, int *rec_offs)
{
        char *p, *q;
        int unpack_size = 88;
        int pathlen, targetlen;

        ENTRY;
        p = buf + pos;
        p = dlogit (&rec->old_parentv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_parentv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_objectv, p, sizeof (struct presto_version));
        p = dlogit (&rec->uid, p, sizeof (int));
        p = dlogit (&rec->gid, p, sizeof (int));
        p = dlogit (&pathlen, p, sizeof (int));
        p = dlogit (&targetlen, p, sizeof (int));

        PRESTO_ALLOC(q, char *, pathlen + 1);
        if (q == NULL) {
                EXIT;
                return -ENOMEM;
        }

        memcpy (q, p, pathlen);
        q[pathlen] = '\0';
        rec->sourcepath = q;

        PRESTO_ALLOC(q, char *, targetlen + 1);
        if (q == NULL) {
                PRESTO_FREE (rec->sourcepath, pathlen + 1);
                EXIT;
                return -ENOMEM;
        }

        memcpy (q, p, targetlen);
        q[targetlen] = '\0';
        rec->targetpath = q;

        *rec_offs = pos + unpack_size + size_round(pathlen) +
                        size_round(targetlen);
        EXIT;
        return 0;
}

static int unpack_mknod (struct kml_mknod *rec, char *buf, 
                                int pos, int *rec_offs)
{
        char *p, *q;
        int unpack_size = 96;
        int pathlen;

        ENTRY;
        p = buf + pos;
        p = dlogit (&rec->old_parentv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_parentv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_objectv, p, sizeof (struct presto_version));
        p = dlogit (&rec->mode, p, sizeof (int));
        p = dlogit (&rec->uid, p, sizeof (int));
        p = dlogit (&rec->gid, p, sizeof (int));
        p = dlogit (&rec->major, p, sizeof (int));
        p = dlogit (&rec->minor, p, sizeof (int));
        p = dlogit (&pathlen, p, sizeof (int));

        PRESTO_ALLOC(q, char *, pathlen + 1);
        if (q == NULL) {
                EXIT;
                return -ENOMEM;
        }

        memcpy (q, p, pathlen);
        q[pathlen] = '\0';
        rec->path = q;

        *rec_offs = pos + unpack_size + size_round(pathlen);
        EXIT;
        return 0;
}

static int unpack_link (struct kml_link *rec, char *buf, 
                                int pos, int *rec_offs)
{
        char *p, *q;
        int unpack_size = 80;
        int pathlen, targetlen;

        ENTRY;
        p = buf + pos;
        p = dlogit (&rec->old_parentv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_parentv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_objectv, p, sizeof (struct presto_version));
        p = dlogit (&pathlen, p, sizeof (int));
        p = dlogit (&targetlen, p, sizeof (int));

        PRESTO_ALLOC(q, char *, pathlen + 1);
        if (q == NULL) {
                EXIT;
                return -ENOMEM;
        }

        memcpy (q, p, pathlen);
        q[pathlen] = '\0';
        rec->sourcepath = q;
        p += size_round (pathlen);

        PRESTO_ALLOC(q, char *, targetlen + 1);
        if (q == NULL) {
                PRESTO_FREE (rec->sourcepath, pathlen + 1);
                EXIT;
                return -ENOMEM;
        }
        memcpy (q, p, targetlen);
        q[targetlen] = '\0';
        rec->targetpath = q;

        *rec_offs = pos + unpack_size + size_round(pathlen) +
                        size_round(targetlen);
        EXIT;
        return 0;
}

static int unpack_rename (struct kml_rename *rec, char *buf, 
                                int pos, int *rec_offs)
{
        char *p, *q;
        int unpack_size = 104;
        int pathlen, targetlen;

        ENTRY;
        p = buf + pos;
        p = dlogit (&rec->old_objectv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_objectv, p, sizeof (struct presto_version));
        p = dlogit (&rec->new_tgtv, p, sizeof (struct presto_version));